Vacuum tube



April zo, 1926., 1581,52

P. SCHWERIN VACUUM TUBE roh 17. 1921 fig f77, 2.

Patented Apr. 2o, 1926.

STATES y Lsslszo Mam" OFFICE.

PAUL SCHWERIN, OF NEW YORK, N. Y.,AASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., .A CORPORATION OF NEW YORK.

'VACUUM TUBE.

Application led March 17, 1921. Serial No. 453,101.

To all whom tmay concern:

Be it known that I, PAUL SCHWERIN, a citizen of the United States, lresiding at New York, Ain the county of Bronx and State of New York, have invented certain vnew and useful Improvements in Vacuum Tubes, of which the following is a full, clear, concise, and exact description.

This invention relates to vacuum tubes and has for an object a structural arrangement of the elements thereof whereby the anode may be subjected to the iniuence of .a cooling agent exterior of the tube.

l `This object is accomplished by so deslgning and arranging the anode within the tube that it is in intimate contact with the inner wall thereof. In order that during the evacuation of the tube, the anode may be out of contact with the wall of the tube to allow theheating of the anode by bombardment without corresponding heating. of

'the glass and to also allow free emission from all the surfaces vof the anode of the gas occluded therein, the tube and anode taper in the same direction and the anode is mounted in the tube for movement longitudinally thereof. Furthermore, the structure of the anode is such as to allow'expansion thereof during the operation of the tube without exerting undue pressure on the wall of the tube. l

A further object of the invention lies in the structural arrangement of the cathode and control electrode whereby the former is maintained taut and the latter is allowed to expand freely when heated during the operation of the tube. This invention will be better understood by having reference" to the following specification and accompanying drawing wherein Fig..1 is a sectional view of a vacuum tube embodying the invention in the process of being evacuated. Fig. 2 is a sectional view of a completed tube in operatin position. Fig. 3 discloses diagrammatic y the sectional outline of one form of anode. Fig. 4 is a reduced perspective view of another form of anode.

The vacuum tube comprises a glass envelo e 1 which is substantially cylindrical and as the reentrant `stems 2 and 3 at the ends thereof. Near the reentrant stem 2 are beads 4 projecting from the inner wall of the vessel 1. From these beads the vessel tapers conically toward the stem 3,l as at 5, for a purpose to be later described. Sealed 1n the stem 2 and su ported therefrom, is the metallic rod 6 which extends nearly to the stem 3 at the other end of the tube. Rad1ally projecting from the free end of the rod 6 are the metallic arms 7 on which are supported the lamentary cables 8 domprismg the cathode the other ends of said cables being attached to the ring or circular bus-bar 9. The ring 9 carries wires 10 projecting in the general direction of the stem 2 and having loops at their free ends. Extending from the stem 2 are the glass arms 11 in which are mounted wires 12, the free ends of which extend throughthe loops in the ends of the wires 10 and are bent over to prevent the loops slipping off the wires. The arms are so arranged that every point on them is more relnoved from the center of the tube than is the tip of the stem. Wires 13 extend from the arms 11 to the ring 9, the intermediate ortions of which wires are coiled to form elical springs by means of which tension is applied to the ring 9. By virtue of this `arrangement as filaments 8 expand during the operation of the tube ythe filaments are kept taut and the ring 9 is maintained in proper position to retain the filaments in the desired relation relative to the other elements of the tube. Leading-in wires 14 and 15 for the cathode are connected with the bus-bar or ring 9 and the rod 6. A r

- Mounted in the stem 3 is the metal rod 16 which carries at its free end the circular 90 plate 17. Rods 18 are attached to the plate -17 and have their free ends slidably mountit will rest Aupon lthe beads 4 but that, when thel tube is arranged in the position; shown in Fig. 2, it will slide into positionv to bring the outer wallthereof into contact with the inner wall ofthe vessel. The structural arrangementof the anode is such that the meta-l composing it may expand under the influence of` heat without substantially. 1n-y creasing its exterior diameter. In Figs 1, 2, and 3 the anode is disclosed as bemg provided with inwardly stamped rldges 24 to allow for expansion of the metal without corresponding increase in its. diameter or effective perimeter. By vlrtue of this arrangement the heating of the anodeA dunng the operation of L the tube causes the anode to fit snugly against the inner wall of the tube but preventsthe possibillty of expansion of the anode cracking the glass of the tube.

lIn Fig. k4: the anode is shown ai being a tubular ,memberV having saw cuts extendlng alternately from one end thereofnearly to the oppositeend. The enclosing wall of the tubular member iscontinuous however, as none of the saw lcuts vextend the full length thereof. Thus, the`expansion ofthe material of the tubular'member will bring together the edges of the' saw cuts without increasing the effective perimeter ofthe anode. It is, of course, understood that other Structural arrangements Vof the anode are capable of performlng the same function. A lead` ing-in wire 25 is sealed in the vessel and connected' to the anode.

'with the positive side of a generator` 26 the negative side of which is connected to the cathode, the latter being heated by the battery 27and the anode is bombarded in sub-l stantially the same manner as is disclosed in the patent to Arnold 1,297,309 to free it ofthe occluded gases without excessively heating the glass ofthe tube. Furthermore, the occluded gases maybe freely emitted from the exterior Wall of the anode as it is not in contact with the glass. When the tube is completed and ready for operation, it is arranged in the position shown inFig. 2 and a cooling medium may be directed against the envelope 1 to carry away heat conlucted from the anode through the glass wa What is claimed is:

` 1. A vacuum tube comprising a glass enclosing vessel havinga tapered portion,A and a tapered metal electrode coaxial therewith and; slidably mounted in' said vessel, the

being limited by the contact of its exterior surface with the interior surface of said tapered portion, and means in said tube fpr limiting the movement of said electrode in the opposite direction.

3. A vacuum tubecomprising a glass en- 'closing vessel having a tapered portion, a.

substantially cylindrical tapered metal electrode having its exterior surface in contact with the inner wall ofthe tapered portionof said vessel, said electrode having inwardly bowed portions whereby the material of said electrode may expand without an increase in the effective perimeter of the cylinder.

4. A vacuum tube comprising a stem having radially extending projections, a metallic post sea-led insaid stem, arms extending radially from said post, abus bar, resilient connections between said projections and said bus bar, filaments fastened to said arms and bus bar, and lead wiresconnected with said post and bus bar.

5. A vacuum tube comprising a stem hav! Y ing radially extendingprojectlons, a met-allic post sealed in said stem, arms extending from said post, an annular bus bar, wires on said projections supporting said bus bar, said wires being coiled intermediateA their ends, filaments fastenedv to said arms and bus bar, and lead wires connected with said post and bus bar.

6. A Vacuum vessel comprising inwardly projecting stems oppositely a post sealed in one stem, rods supported by sald post and extending. longitudinally of said post, an annular member supported by the other stem and having apertures through which extend free ends of said rods and a conductor helically wound around said rods.

7. A vacuum vessel comprising inwardly projecting stems oppositely disposed therein, a'post sealed in one stem, a circular plate carr1ed by said post, rods carrie-d by said plate and extendin longitudinally of the post, an annular mem er supported by the other stem having apertures through which extend the free ends of said rods, and a conductor helically wound around said rod.-

8. A vacuum tube comprising a stem having radially extending projections, ametallic post sealed in said stem, arms extending radlally from said post, a bus bar resiliently disposed therein,

lis

attached to said pro'ections, laments fas- 4 9. A vacuum tube comprising a substanjacent thereto, a cathode supported by said tially cylindrical vessel hui-'ing inwardly proother post and means resihently fastening jecting stems at either end, n metallic post said cathode to the stem in which it its sup- 10 sealed in euch stem, n control electrode supporting post is sealed.

5 ported :it one em by one of said posts, ex- In Witness whereof, I hereunto subscribe pansible connections between the other end my name this 11th day of March A. D., 1921. of said control electro-de and the stem ad- PAUL SCHVERIN. 

